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41.
We studied 17 pedigrees with 108 affected males with X-linked juvenile retinoschisis (RS; McKusick No. 31270) and have analyzed all of the known polymorphic markers in the RS region of Xp22.1-p22.2 between DXS987 and DXS41. By haplotype analyses we found 7 individuals who showed crossovers in this interval surrounding RS. We previously reported AFM291wf5 as the centromeric boundary, and this remains unchanged in the present study. A new recombination was identified on the telomeric side at (DXS1195, DXS418). Our data support the locus order Xpter--(DXS987, DXS207, DXS1053, DXS43)--(DXS1195, DXS418)--(RS, DXS257, DXS999)--(AFM291wf5, DXS443)--DXS1052--(DXS1226, DXS274, DXS41)--Xcen; loci grouped in parentheses could not be mutually ordered by our genetic data. Physical mapping has indicated a distance of at most 900-1,000 kb between (DXS1195, DXS418) and AFM291wf5. No recombination was observed between RS and DXS257 which lies in our new interval of interest, but one critical individual was not informative with this marker. Our data now define the smallest RS inclusion interval. This interval is contained on a single YAC from which we have identified expressed sequences as candidate genes for RS.  相似文献   
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Forty-nine pairs of bilateral breast tumors (41 synchronous and 8 asynchronous cases) were examined for X-chromosome inactivation status and p53 mutations to address the issue of their clonality. Among 12 cases that were informative for the trinucleotide repeat polymorphism in exon 1 of the androgen receptor gene on the X chromosome, 3 cases were found to have different alleles of the locus inactivated in the right and left breast tumors, indicating that the two tumors arose from distinct transformed cells. Thirteen tumors (13%) from 11 women (22%) contained somatic mutations in exons 5-8 of the p53 gene. In two cases, both breast tumors harbored p53 mutations, but the specific mutations were not identical. Seven synchronous and two asynchronous cases had p53 mutations in one tumor only. A germ line p53 mutation at codon 248, one of the most common p53 mutations in Li-Fraumeni syndrome, was observed in one case. Immunohistochemical analysis of p53 protein with a monoclonal antihuman p53 antibody showed concordant positivity between the right and left tumors in three bilateral breast cancer cases. Our results suggest that at least some bilateral breast tumors originate from distinct cells, but that some bilateral breast tumors may be related through a common p53 abnormality.  相似文献   
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Basic fibroblast growth factor (bFGF), a prototypic member of a family of heparin-binding growth factors, is angiogenic both in vitro and in vivo. Increased levels and activity of bFGF have been documented in a variety of diseases, including tumors. We sought to determine whether bFGF might be similarly elevated in patients with clinical evidence of limb ischemia. Serum was obtained at the time of percutaneous revascularization from patients with symptomatic peripheral vascular disease (46 procedures were performed on 40 patients). An enzyme-linked immunoassay specific for bFGF was used (limit of detection, 1 pg/ml; range in normal subjects, 0 to 5 pg/ml). Among the 40 patients (28 men, 12 women, mean age 70 years) studied, elevated circulating bFGF (> or = 10 pg/ml) was detected in 36 samples (78%); levels ranged from 10 to 310 pg/ml (mean +/- SEM = 62 +/- 12). In 16 (89%) of 18 patients with both rest pain and nonhealing ischemic ulcers, serum bFGF levels were elevated up to 30 times normal values. In conclusion, circulating levels of bFGF are elevated in patients with vascular insufficiency and may reflect a physiologic response to limb ischemia.  相似文献   
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Ulex europaeus isolectin I is specific for fucose-containing oligosaccharide such as H type 2 trisaccharide alpha-L-Fuc (1-->2) beta-D-Gal (1-->4) beta-D-GlcNAc. Several legume lectins have been crystallized and modeled, but no structural data are available concerning such fucose-binding lectin. The three-dimensional structure of Ulex europaeus isolectin I has been constructed using seven legume lectins for which high-resolution crystal structures were available. Some conserved water molecules, as well as the structural cations, were taken into account for building the model. In the predicted binding site, the most probable locations of the secondary hydroxyl groups were determined using the GRID method. Several possible orientations could be determined for a fucose residue. All of the four possible conformations compatible with energy calculations display several hydrogen bonds with Asp-87 and Ser-132 and a stacking interaction with Tyr-220 and Phe-136. In two orientations, the O-3 and O-4 hydroxyl groups of fucose are the most buried ones, whereas two other, the O-2 and O-3 hydroxyl groups are at the bottom of the site. Possible docking modes are also studied by analysis of the hydrophobic and hydrophilic surfaces for both the ligand and the protein. The SCORE method allows for a quantitative evaluation of the complementarity of these surfaces, on the basis of molecular lipophilicity calculations. The predictions presented here are compared with known biochemical data.  相似文献   
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PURPOSE: To investigate if double modulation of fluorouracil (5-FU) with leucovorin (folinic acid [FA]) and interferon alfa-2b (IFN 2b) improves responses and survival in comparison to single modulation of 5-FU with FA. PATIENTS AND METHODS: One hundred six patients with histologically confirmed advanced colorectal cancer, measurable disease, and without previous chemotherapy were prospectively randomized into two groups. Patients in group A received 5-FU 450 mg/m2 as an intravenous bolus in the midinfusion of FA weekly. FA was given at a dose of 200 mg/m2 in 500 mL 0.9% normal saline solution in 2-hour infusion. Patients in group B received exactly the same regimen plus IFN 2b 5 million units subcutaneously three times weekly. RESULTS: All patients were well balanced in both groups regarding age, sex, performance status, number, and site of metastasis. One hundred two patients were assessable. All patients have died. There was no difference in response between the two groups (7.8% v 9.8%). Median survival was 10.1 months in group A, and 7.2 months in group B (P = .00189). Median time to progression was 8.4 and 5.2 months, respectively (P = .00196). Overall, better performance status and older age had a positive impact on survival. Toxicity was the most important and catastrophic aspect of this study. Patients who received IFN 2b had significantly worse anemia, neutropenia, diarrhea, anorexia, weight loss, flu-like syndrome, and psychological reactions. CONCLUSION: Based on this final analysis, the addition of IFN 2b to the combination of 5-FU and FA enhances toxicity and contributes to decreased survival.  相似文献   
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OBJECTIVE: To explore the feasibility of recruiting, training, and placing in the field volunteers to assist community practices in enhancing the provision of preventive care. DESIGN: A case series design followed up a cohort of volunteers prospectively as they were recruited, trained, and assigned to practices. SETTING: The New Hampshire Division of the American Cancer Society recruited and trained the volunteer facilitators. INTERVENTION: Assistance from the volunteers in implementing a preventive services office system served as the intervention for practices. Volunteers were trained and supported by professional staff and an implementation manual. MAIN OUTCOME MEASURES: Recruitment, training, and volunteer experiences in working with practices, as well as the costs of supporting the program, were assessed. RESULTS: Twenty-six volunteers were trained. Of the 15 assigned to practices, 11 had begun to assist their assigned practices to establish a preventive services office system. Extensive planning, patience, and support were required. CONCLUSION: Volunteers recruited and supported by an intermediary organization can provide assistance to practices in implementing a preventive services office system.  相似文献   
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